Subject: [tsvwg] Last Call: <draft-ietf-tsvwg-datagram-plpmtud-15.txt> (Packetization Layer Path MTU Discovery for Datagram Transports) to Proposed Standard

From: The IESG <[email-masked]>
Date: Tue, 25 Feb 2020 06:14:05 -0800

The IESG has received a request from the Transport Area Working Group WG
(tsvwg) to consider the following document: - 'Packetization Layer Path MTU
Discovery for Datagram Transports'
  <draft-ietf-tsvwg-datagram-plpmtud-15.txt> as Proposed Standard

The IESG plans to make a decision in the next few weeks, and solicits final
comments on this action. Please send substantive comments to the
[email-masked] mailing lists by 2020-03-10. Exceptionally, comments may
be sent to [email-masked] instead. In either case, please retain the beginning
of the Subject line to allow automated sorting.

Abstract

   This document describes a robust method for Path MTU Discovery
   (PMTUD) for datagram Packetization Layers (PLs).  It describes an
   extension to RFC 1191 and RFC 8201, which specifies ICMP-based Path
   MTU Discovery for IPv4 and IPv6.  The method allows a PL, or a
   datagram application that uses a PL, to discover whether a network
   path can support the current size of datagram.  This can be used to
   detect and reduce the message size when a sender encounters a packet
   black hole (where packets are discarded).  The method can probe a
   network path with progressively larger packets to discover whether
   the maximum packet size can be increased.  This allows a sender to
   determine an appropriate packet size, providing functionality for
   datagram transports that is equivalent to the Packetization Layer
   PMTUD specification for TCP, specified in RFC 4821.

   The document updates RFC 4821 to specify the method for datagram PLs,
   and updates RFC 8085 as the method to use in place of RFC 4821 with
   UDP datagrams.  Section 7.3 of RFC4960 recommends an endpoint apply
   the techniques in RFC 4821 on a per-destination-address basis.  RFC
   4960, RFC 6951 and RFC 8261 are updated to recommend that SCTP, SCTP
   encapsulated in UDP and SCTP encapsulated in DTLS use the method
   specified in this document instead of the method in RFC 4821.

   The document also provides implementation notes for incorporating
   Datagram PMTUD into IETF datagram transports or applications that use
   datagram transports.

   When published, this specification updates RFC 4960, RFC 4821, RFC
   8085 and RFC 8261.

The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-tsvwg-datagram-plpmtud/

IESG discussion can be tracked via
https://datatracker.ietf.org/doc/draft-ietf-tsvwg-datagram-plpmtud/ballot/

No IPR declarations have been submitted directly on this I-D.